THE NIGHT OF TOO MANY STARS: AMERICA COMES TOGETHER
Comedy Central, 8:00 p.m. ET
This fundraising event for autism-related charities is, essentially, a party thrown by the coolest kids in class. Jon Stewart is the host, and performers include everyone from Stephen Colbert and Louis C.K. to Katy Perry (pictured, performing with Jodi DiPiazza) and Tina Fey and Amy Poehler. Watch the Perry-DiPiazza clip on Video Worth Watching... and then dry your eyes.